Population Pharmacokinetics of Cephalosporins and Macrolides in Chinese Children With Community Acquired Pneumonia

Inclusion Criteria: * Children 1-18 years old of both sexes, with a diagnosis of community acquired pneumonia and eligible for treatment with cephalosporins and macrolide antibiotics, as per current treatment protocols. * Community acquired pneumonia diagnostic criteria: meet any one of the 1-4 following items plus the fifth item: * 1\. With cough, expectoration, or pre-existing respiratory disease getting worse, and with purulent sputum with or without chest pain; * 2\. Fever; * 3\. With pulmonary consolidation and crackles; * 4\. White blood cells\>10×10\^9/L or \<4×10\^9/L; * 5\. X-ray on chest shows flake, patchy infiltrate shadows or interstitial changes, with or without pleural effusion. * Informed consent signed by the parents, and consent or assent of the patients (according to age and consenting capacity). Exclusion Criteria: * It is unable to provide complete medical records or the current condition can not accept the diagnosis process. * It does not agree to participate in this study.